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NumPy array creation: empty() function

empty() function

The empty() function is used to create a new array of given shape and type, without initializing entries.

Syntax:

numpy.empty(shape, dtype=float, order='C')
NumPy array: empty() function

Version: 1.15.0

Parameter:

Name Description Required /
Optional
shape Shape of the empty array, e.g., (2, 3) or 2. Required
dtype Desired output data-type for the array, e.g, numpy.int8. Default is numpy.float64. optional
order Whether to store multi-dimensional data in row-major (C-style) or column-major (Fortran-style) order in memory. optional

Return value:

[ndarray] Array of uninitialized (arbitrary) data of the given shape, dtype, and order. Object arrays will be initialized to None.

Example: numpy.empty() function

>>> import numpy as np 
>>> np.empty(2)
array([  6.95033087e-310,   1.69970835e-316])
>>> np.empty(32)
array([  6.95033087e-310,   1.65350412e-316,   6.95032869e-310,
         6.95032869e-310,   6.95033051e-310,   6.95033014e-310,
         6.95033165e-310,   6.95033167e-310,   6.95033163e-310,
         6.95032955e-310,   6.95033162e-310,   6.95033166e-310,
         6.95033160e-310,   6.95033163e-310,   6.95033162e-310,
         6.95033167e-310,   6.95033167e-310,   6.95033167e-310,
         6.95033167e-310,   6.95033158e-310,   6.95033160e-310,
         6.95033164e-310,   6.95033162e-310,   6.95033051e-310,
         6.95033161e-310,   6.95033051e-310,   6.95033013e-310,
         6.95033166e-310,   6.95033161e-310,   2.97403466e+289,
         7.55774284e+091,   1.31611495e+294])
>>> np.empty([2, 2])
array([[7.74860419e-304, 8.32155212e-317],
       [0.00000000e+000, 0.00000000e+000]])
>>> np.empty([2, 3])
array([[  6.95033087e-310,   1.68240973e-316,   6.95032825e-310],
       [  6.95032825e-310,   6.95032825e-310,   6.95032825e-310]])

Pictorial Presentation:

NumPy array: empty() function

Example: numpy.empty() where data-type for the array is int

>>>import numpy as np
>>> np.empty([2, 2], dtype=int)
array([[140144669465496,        16250304],
       [140144685653488, 140144685468840]])
>>> np.empty([2, 2], dtype=float)
array([[2.37015306e-316, 7.37071328e-315],
       [9.06655519e-317, 2.00753892e-317]])

Pictorial Presentation:

NumPy array: empty() function

Python - NumPy Code Editor:

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